When brake fluid boil occurs, it makes the brake pedal feel spongy or go straight to the floor when applied. @autoedits_jason explains that during periods of increased braking such as mountainous driving, trailer towing, or high-speed stops, heat can be transferred to the brake caliper, dramatically increasing the brake fluid temperature. Brake fluid naturally attracts and absorbs water. If the fluid has absorbed water, the boiling point is reduced dramatically. Between the increase in temperatu